package com.example.Interceptor;

import com.alibaba.fastjson.JSON;
import com.baomidou.mybatisplus.core.toolkit.ObjectUtils;
import com.example.Result.Result;
import com.example.context.BaseContext;
import com.example.util.JwtUtil;
import io.jsonwebtoken.Claims;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import lombok.extern.slf4j.Slf4j;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.stereotype.Component;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;

import java.io.PrintWriter;


/**
 * jwt令牌校验的拦截器
 */
@Component
@Slf4j
@Configuration
public class JwtTokenUserInterceptor implements HandlerInterceptor {

    /**
     * 校验jwt
     *
     * @param request
     * @param response
     * @param handler
     * @return
     * @throws Exception
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        //判断当前拦截到的是Controller的方法还是其他资源
        if (!(handler instanceof HandlerMethod)) {
            //当前拦截到的不是动态方法，直接放行
            return true;
        }

        //1、从请求头中获取令牌
        String token = request.getHeader("token");
        System.out.println(token);

        if (token == null) {
            Result result = Result.error("用户未登录，请重新登录");
            String jsonStr = JSON.toJSONString(result);
            response.setContentType("application/json;charset=UTF-8");
            PrintWriter out = response.getWriter();
            response.getWriter()
                    .write(jsonStr);
            return false;
        }

        //2、校验令牌
        try {
            log.info("jwt校验:{}", token);
            Claims claims = JwtUtil.parseJWT("sziit", token);

            if (ObjectUtils.isNull(claims)) {
                Result result = Result.error("登录已过期，请重新登录");
                String jsonStr = JSON.toJSONString(result);
                response.setContentType("application/json;charset=UTF-8");
                PrintWriter out = response.getWriter();
                response.getWriter()
                        .write(jsonStr);
                return false;
            }
            Integer empId = (Integer) claims.get("userId");
            log.info("当前员工id：", empId);
            BaseContext.setCurrentId(empId);
            //3、通过，放行
            return true;
        } catch (Exception ex) {
            //4、不通过，响应401状态码
            response.setStatus(0);
            response.setCharacterEncoding("utf-8");
            response.getWriter().write(ex.getMessage());
            return false;
        }
    }
}
